Asked for a bar chart of the route legs, a Claude Code session edits scripts/route.jl, runs it in the shared Julia REPL and shows the chart in the preview. The whole window: the file tree, the preview, the Julia drawer, the agent column and, along the bottom, the session strip, where a script sets the other demo sessions' colors (sped up).
A desktop window, drawn on the GPU, with a keyboard-driven layout: a navigation tree, a file preview, an agent pane, a Julia REPL drawer and, along the bottom, the session strip. The status:, annotation: and key: lines around the tree are plain readouts; The interface says what each shows.
CairoMakie figures appear inline; interactive WGLMakie figures and Pluto notebooks open in your browser. Because the window draws all of this itself, it needs a graphical desktop, not a terminal. Linux; Windows and macOS run as frontends to a Linux backend (macOS is experimental). See Platforms.
Several agents, one list
Every agent session is a row in Sessions mode, on this machine or on any connected host. The row color is the agent's work state, so you can see which session needs you without opening each one. Shift+Right / Shift+Left switch sessions; each session keeps its own Julia REPL, and switching never restarts it.
Demo session rows changing color as a script sets their work states: green working, red waiting for your answer, purple waiting on a job, blue done, gray idle. Each row's [ready] tag means its session process is up. Under the rows, the session strip shows the same colors.
Navigate the project, see the file
The navigation pane is a tree whose root you switch with one key: f for files, m for modules and their definitions, s for sessions, h for hosts. The preview pane renders the entry under the cursor: markdown with typeset math, paged PDF, images, HDF5 structure, syntax-highlighted Julia.
The preview follows the cursor through notes with math, the agent's bar chart, an HDF5 file, a PDF and the route figure.
Your machines as one workspace
The backend runs where the data and GPUs are; the window runs on your laptop or desktop and attaches over SSH. Sessions, REPLs and agents keep running on a remote server when the lid closes or the window restarts (closing the window ends the sessions of a backend on the same computer, not those of a remote one), and several windows can attach to one backend. See Going remote.
Extend in Julia
A preview for a new file type is a Julia plugin: a FileType subtype with a matches method and a preview method, with no Rust changes. This one shows a CSV file as a markdown table. The built-in text, source, PDF and video previews use the same interface. A plugin is added to the kernel's own environment in a source checkout; nothing discovers a package of yours by itself (see Discovery). The HDF5 preview tutorial shows one.
julia
struct CsvFile <: FileType endConceptExplorerCore.matches(::Type{CsvFile}, path) = endswith(lowercase(path), ".csv")function ConceptExplorerCore.preview(::Type{CsvFile}, path) # ... build a PreviewPayload of "text/markdown" from the CSV rowsend
Frontend and backend together on one Linux machine. For a remote backend (install and enroll the backend first: the hub's hosts.toml must list this machine), a second frontend or Windows, see Going remote and Install details, which also lists what the installer writes and how to remove it. What it touches:
Everything goes under your home directory, mostly ~/.local/share/sot, plus user lingering so the backend keeps running after logout on Linux.
Skills and hooks go into your global ~/.claude and ~/.codex; a skill of yours with the same name as a shipped one is overwritten without a backup.
Sessions start their agent with fixed permission flags: Claude Code in auto mode; Codex with approvals, the sandbox and hook trust all bypassed.
![Demo session rows changing color as a script sets their work states: green working, red waiting for your answer, purple waiting on a job, blue done, gray idle. Each row's [ready] tag means its session process is up. Under the rows, the session strip shows the same colors.](/ship-of-tools/stable/assets/sessions.RlFceyE0.png)
